Project Summary/Abstract Physical Sciences, Inc. (PSI), in collaboration with The Forsyth Institute, Cambridge, MA is proposing to develop a technology that will address a major unmet medical need in periodontology: the lack of tools to quantitatively and objectively assess the health/disease status of the gingival soft tissues. The proposed technology will combine high resolution micro-Optical Coherence Tomography with Raman microspectroscopy for in vivo assessment of periodontal tissue integrity and therapy guidance. Both Raman and OCT are powerful technologies with proven success in human tissue imaging, avoiding the need for ionizing radiation exposures. While OCT allows for the visualization of soft tissue anatomy, Raman is used to interrogate the biochemical composition of gingival tissues, as indicators of structural integrity. The complementary capabilities of these two optical technologies will be exploited to offer a clinically comprehensive set of parameters to more reliably and precisely determine the periodontal health status. During the Phase I program we performed a preliminary investigation of this powerful dual-mode optical approach and demonstrated its capability for highlighting periodontal tissue morphological and biochemical changes that are not otherwise visible using any current clinically-available tools. The Phase I data indicated the potential of this technology for assisting clinicians in the diagnosis of periodontal health status. In Phase II we propose to develop a clinically viable instrument, optimize it, and clinically evaluate its capability for assessing patient periodontal health. In addition, during Phase II program, preliminary steps for technology commercialization and FDA regulatory approval will be taken. This innovative technology is of great clinical significance as it could provide clinicians with a novel diagnostic tool to detect early signs of periodontitis and accurately measure changes in intrinsic tissue properties to monitor disease activity in response to therapy. These will in turn allow for individualized therapeutic approaches for individuals at risk and poor responders to conventional therapy, with significant potential for improving prevention and lowering healthcare costs. Once validated for periodontal tissue, future applications may include the assessment of soft tissues around dental implants for early diagnosis of peri- implant diseases.